The northeastern United States has had a record early spring.  Ice-out on Lake Winnepesaukee, New Hampshire, occurred several days earlier than the previous record.   As far north as eastern Massachusetts, rattlesnakes were seen in mid-March.    Temperatures from the Ozarks and southern Appalachians northward ran 6-12 degrees F above average for the first half of April, and 4-8 degrees F above for the entire month, with the greatest departure from normal toward the northeast. 
             James Condon saw a rattlesnake on 12 March in eastern Massachusetts. Randy et al saw a few in the Hudson Highlands around 18-21 March and I got a report of one in eastern Massachusetts on 12 March.  Lake Winnepesaukee, NH had a record early ice-out.   The earliest previous date on which I ever saw 10 or more was 9 April (1991) but recall, that on 3 April, ‘07, Jim McGibney saw 13 in northern Maryland.  Typically my first good day (10 or more TR) falls between 15 and 22 April. 
            Roger Arnold passed on an observation of a rattlesnake found early April in Goochland County, Virginia near the James River.  This represents a major extension beyond the known range. Expect details shortly.
            I saw 10 and 4 at two dens in the AT (Appalachian Trail) corridor along the Virginia/West Virginia line on 5 April.   On 7 April I saw about 25 at a southeast facing den between 1400 and 1500 ft in northern Maryland; a precise count was not possible but one pile at the mouth of a hibernating crevice consisted of about 10 snakes, plus or minus one or two. At a southerly facing den of similar elevation under heavy canopy I saw three and then at the west-facing hibernaculum 130 meters away, nothing.  (These two typically run a couple of days apart.)  The following day 8 April, I was in Shenandoah NP and checked two of the earlier dens, one a horizontal fissure at a very open rock face of 2000 ft elevation and the other a complex in scree and ledge under the canopy from 1700-1825 ft.   No snakes were seen. Apples and peaches both reached full bloom that day in the Shenandoah Valley where I live.  Peaches typically precede apples by 1-2 weeks.  The earliest previous blooms for apples were three times on 15 April.  April 26-28 is typical.
            I missed a couple of field days when I attended Project Orianne’s Upland Snake Initiative meeting in south Georgia on 12-13 April.  It does look like we will have an Eastern Diamondback Conservation Plan with the first meeting a the Gopher Tortoise Council meeting in south Alabama in October.
            We apparently had peak emergence at our lower elevations in mid-April, about a week ahead of average.   On 15 April I saw 29 TR at a southerly facing 1200 ft den and then on 16 April five TR at an easterly facing 1200 ft den and 29 at a 1200-1625 ft den complex.  Sites visited were in Virginia and West Virginia, all near the state line.
            With Lance Benedict on 20 April at an easterly facing den of 900 ft elevation at a northern Virginia Piedmont monadnock we saw three big males of about 54, 53, and 46 inches.  At a westerly facing site of about 800 feet we found another big male of about 45 inches that had moved about 50 meters from the hibernaculum. 
            On 22 April with daughter Claire, Lance Benedict, Jay Rubinoff, Barbara Watkins of National Zoo,  in northern Maryland—eight Timbers at a 1300 ft elevation easterly facing den which I had initially visited in late April of ’69 and seen three TRs. (No interim den visits but 6 gestating females were seen in ’09.) Then 26 at the same den I had visited on 7 April, and 15 at a long-term monitoring den of about 1600 ft for a day’s total of 49 plus two copperheads. One of the day’s snakes was “in blue” the earliest date on which I have recorded a sTR as pre-shed.  (The spring shed typically occurs 4-6 weeks after emergence and only rarely have I seen post-shed snakes as early as late May. The bright fresh looking snakes one sees in the spring are those that shed the previous September.)   On 23 April Lance and I returned to the same two Shenandoah dens I visited on 8 April and saw 10 and 10 TRs.

            The early warm-up got snakes at some dens on the surface 2 weeks ahead of the typical time in the central Appalachians and perhaps 3 weeks early in the Northeast.  The early leafing, however, shaded many of the dens thus retarding further warming.   Apparently we have had a general emergence at the lower elevations of the central Appalachians peaking around 15-16 April and around 24 April at the lower elevations of the Hudson Highlands of New Jersey and New York.  Some emergence has apparently occurred at the higher elevations and to an even greater extent at the higher latitudes.   I anticipate peak emergence in much of the central Appalachian region during the period 30 April to 2 May, dates that are not much different from what is typical. *Note-the above summary paragraph was written on 29 April.

4 May. Two Shenandoah NP dens, one about 2450 and the other 2200 and 2450 at its lower and upper parts—10 and 8 TR respectively, a bit past peak emergence.
5 May. With Lance Benedict and Ben Markel at a 3200 ft Shenandoah site—four adults,  one moving out about 200 meters below the den, one at the rookery, and two at the den.  Probably a day before peak emergence.   
Then at a 2800 foot site—one TR about 10 meters from the gestating site which was just discovered in summer ‘09. 
The following two days 6 and 7 May Lance returned to Shenandoah and at a normally late den of 2550 feet, saw 16 and 17 respectively.
7 May, I was at a 3100 foot den on the High Allegheny Plateau of West Virginia and saw 7—6 adults (one male) at the basking area and a 3-yr old at probable hibernating area.  I had last been here in June of 1998. 
            Here in the central Appalachian region general emergence apparently started by 2 April at some low-elevation and other normally early dens. Emergence apparently peaked at these early dens by 15 April and essentially all snakes were on the surface and out of these dens by 25 April.  A widespread general emergence apparently occurred during the period of 15 April to 30 April with most snakes at higher latitudes and elevations on the surface by 7 May.  Considerable cool and rainy weather during the period of 8-19 May (14 May the only hot day in the period) held some snakes at the higher-elevation/higher latitude basking sites until hot weather returned 20-25 May.   My last field day in the area was 14 May at a fairly low elevation den (1400 ft) and two were seen in the den and three at a nearby basking area. 
            In 2009 many sites, but by no means all sites, in the central Appalachians experienced very high reproduction.   The factors influencing reproduction are ….1) intrinsic cycle based on a minimum birthing interval of 2 years, breeding taking place the last half of the active season in the year prior to giving birth; 2) reproductive history (gestating females are not available to breed during the year they give birth); 3) availability of prey, especially during the first half of the active season (prey availability is heavily influenced by the red oak crop of the previous fall.);  4) weather during the first half of the active season of the breeding year. (cool and wet weather inhibits feeding and fat storage).     So, given the high reproduction experienced in may areas in  2009, the somewhat wet and cool first half of the 2009 active season,  a low to moderate reproduction is to be expected in most areas.  Areas that experienced a low reproduction in 2009 might be expected to have a higher reproduction in 2010.  

            Emergence was pretty much over by mid-May. Under favorable weather conditions on 14 May I checked a nearby Blue Ridge den of about 1400 ft.  Only two snakes, an adult female and a 2-yr old juvenile were still in the den. Three adults, including a 50 inch male were at a shedding site about 75 meters distant.  The same day Lance Benedict checked a high elevation (3300 ft) Blue Ridge den farther south and saw  four TR, three of which were at a gestating site.   Few or no snakes were reportedly seen in northern Maryland on the weekend of 15-16 May.
            Hoping that there were still some snakes in the dens farther north Lance Benedict and I headed towards north-central Pennsylvania on Thursday 19 May.  En route we checked a site I had found in cold weather on a wind-farm project.  The site is a southwest-facing scree slope just above the highway at about 2250 feet.  The weather was poor---low 50s and no sun.  We saw seven adults, four at one big slab and three at another.  Most appeared to be gravid females. 
            The following morning in north-central Pennsylvania we checked another site I had found in cold weather on a wind-farm project.  It is a south-facing scree of not much vertical extent but extending intermittently for about 200 metes along the breakover of a flat at about 2100 ft.  We saw 33 TR and heard two more at the denning/basking areas.  Mostly adults were seen, including a big male about 50 inches in length.  Two additional adult males were encountered on the wooded flat 100-200 meters from the denning areas.
            In the afternoon, sunny and mid 70s, we checked a nearby site of similar elevation which I had last visited on the same day (5/20) in 1980 with Steve Harwig.   This time we saw 15 total.  Two, a juvenile and sub-adult were in the shaded hibernaculum about 200 meters from the open scree where the balance, 9 adults and 4 subadults around 28-30 inches were located at two slabs.   An adult male was shedding---one of the earliest sheddings I have noted. 
            The following day we headed up to Allegheny National Forest in northwest Pennsylvania.  We saw six together—all big adults except for a sub-adult (5+b) of about 33 inches at a southeast facing ledge of about 1650 feet.  Shading over is a major problem in northwest Pennsylvania but this ledge had been cut over in recent years.
            Then we headed over to an area where I had seen 16 TR with Steve Harwig (5/21/76) in the vicinity of a headwater stream flowing through an area of intermittent woods with a number of rocky patches near the stream. Elevations are 1500-1550. We only saw three this time but found the overwintering den about 200 meters from the stream head on a wooded hillside facing west-northwest at 1625 ft.  Three snakes were at two hibernating crevices and 7 large adults—most appeared to be gravid—were crowded together at the only rock that got full sun.   Again this was exactly 34 years to the day from the previous trip when we speculated that the snakes might have overwintered in the rocky meadow near the stream.
            Northwest Pennsylvania west of 219 and north of I 80, for the most part, has much less relief than does north-central which has been heavily dissected by streams.   Rather than the scree slopes that occur over most of the mountainous parts of the state most dens are located in big ledges of level lying sandstone with a vertical side often 10-20 feet high.  Many of these ledges have either been overtopped by trees growing up from the base or by trees and shrubs encroaching from the top and growing out toward the rim.  A similar situation although less severe is noted farther south where the geology is similar on parts of the Allegheny and Cumberland Plateaus of West Virginia and southwest Virginia.
            For two periods totaling 7 days from 8 to 17 June I was back in north-central Pennsylvania assessing rattlesnake habitat on a 78-mile east-west pipeline project and found a total of 45 TR at 14 different sites along the line.   Shedding peaked during the period.  Several sites had 4-6 gravid females.   Meanwhile Lance continued to check local sites seeing up to 18 snakes at a site.
            Indications thus far are for a low to moderate reproduction. Expect births to run 2-3 weeks earlier than the average with first young born around 1 August and births peaking in mid-August. Judging from the extremely high density of red oak seedlings this spring there should have been an abundance of mice and chipmunks.  Coupled with the high temperatures there should be plenty of snakes breeding later this summer starting about mid-July. 

 

W. H. Martin
whmartin@crotalus.org
Flat Earth Lane
1227 Engle Molers Rd.
Harpers Ferry, WV 25425
(304) 876-3219

 

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